Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Comparison of Rainfall Seepage Characteristics of Gneiss and Granite Weathered Soil

편마암풍화토와 화강암풍화토의 강우 침투특성 비교

  • Song, Young-Suk (Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Yoo, Yong-Jae (Dept. of Civil and Environmental Engrg., Dongshin Univ.) ;
  • Kim, Tae-Wan (Dept. of Civil and Environmental Engrg., Dongshin Univ.) ;
  • Kim, Jae-Hong (Dept. of Civil and Environmental Engrg., Dongshin Univ.)
  • 송영석 (한국지질자원연구원 지질환경연구본부) ;
  • 유용재 (동신대학교 토목환경공학과) ;
  • 김태완 (동신대학교 토목환경공학과) ;
  • 김재홍 (동신대학교 토목환경공학과)
  • Received : 2021.04.09
  • Accepted : 2021.05.13
  • Published : 2021.06.30
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Abstract

The factors of landslides depend on rainfall intensity, duration, and the characteristics of the soil slope. The conventional slope stability analysis has been carried out by assuming that the slope is saturated. But, a site slope consisting of unsaturated ground must be imitated and interpreted in order to explain a proper behavior of the slope due to rainfall. In this study, by using two major categories of soils in Korea, such as granite and gneiss weathered soils, landslide model test and numerical analysis have been compared with the difference of seepage and volumetric water content. In general, the permeability of gneiss weathered soil, which contains a lot of fines content, is slower than that of granite weathered soil. As a result, in extreme rainfall, numerical analysis can show results that can penetrate quickly, resulting in saturation or more dangerous collapse.

산사태의 원인들은 강우강도와 강우지속시간 그리고 사면의 함수특성에 따라 좌우된다. 기존의 사면안정해석에서는 사면을 포화토로 가정하여 해석해왔다. 그러나 강우로 인한 적절한 사면의 거동을 설명하기 위해서는 불포화지반으로 구성되어 있는 현장사면을 모사하여 해석해야 한다. 본 연구에서는 국내 주요한 산지를 구성하고 있는 지반인 화강풍화토와 편마암풍화토를 구분하여 비탈면붕괴에대한 실내모형시험과 수치해석을 병행하여 강우침투와 사면의 안정성에 대해서 분석하고자 하였다. 일반적으로 세립분을 많이 포함하고 있는 편마암풍화토의 투수계수는 화강풍화토의 투수계수보다 느리다. 이러한 조건의 특징을 활용하여 두 가지 다른 풍화토의 침투량을 체적함수비 센서를 활용하여 강우로 인한 표층의 침투특성을 실내시험과 수치해석으로 비교하고자 한다.

Keywords

Acknowledgement

이 논문은 한국지질자원연구원 기본사업인 "실시간 도시지역 산사태 조기경보기술 및 지질환경 오염물질 위험관리기술 개발(21-3412-1)" 과제와 2021년도 동신대학교대학원 대학혁신지원사업(DS-콜로키움)에서 지원받았으며, 정부(교육부)의 재원으로 한국연구재단의 지원을 받아 수행된 기초연구사업임(No. 2020R1I1A307511011).

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